Pencil-sharpener.



E. WEILBR.

PENCIL SHABPENEB. -ArrLloA'rIoN rum 11,111.5, 1910.

Patented Ju1y5,.1910.

ERNST WEILER, OF BERLIN, GERMANY.

:PENCIL-SHARPENER.

Specification of Letters Patent.

Patented July 5, 1910.

Application filed 'March 5, 1910. Serial No. 547,562.

To all whom it may concern: v

Be it known that I, ERNST WEILER, mechanic, a citizen y of the German Empire, residing at Berlin, in the Kingdom of Prus- Sia, Germany, have invented certain new and useful Improvements in Pencil-Sharpeners; and I do hereby declare the following to be a full, clear, and eXact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in pencil Sharpeners, and more particularly to that class of Sharpeners in which an eX- changeable blade is provided.

The object of the improvements is to provide a Sharpener in which the exchangeable blade adapts itself perfectly to the form of its bearing surface, So that the Same blade may be used in Sharpeners in which the cutting edge of the blade is straight, or in which the said edge is curved, as is the case in Sharpeners which are used for cutting a curved ir hollow point on the pencil.

With this object in view my invention consists in providing my improved pencil Sharpener with a flexible blade. In order to have the required flexibility the blade is formed of very thin metal strips. By thus constructing the blade of thin metal I obtain the further advantage, that the edge has a longer life, than blades of ordinary thickness. Furthermore the cost of such a blade is considerably below that of the ordinary blades, So that a large number of blades can be supplied with the Sharpener without materially increasing its cost. This is particularly advantageous, because it is difficult for a non-expert to properly grind the blades and afterward correctly fit the same in the Sharpener. Such fitting must be edected with considerable accuracy, an inaccuracy of about one twentieth of a millimeter being detrimental to the satisfactory operation of the Sharpener. In order to decrease the cost of the blade, I have found it advisable t0 reduce its thickness to 0.2 millimeter.

A further object of the improvements is to provide a cavity in my improved sharpener which is adapted for the reception of a plurality of thin blades which may be supplied with the Sharpener.

a removable sleeve forming a suitable guide for pencils of normal diameter, and which when removed permits the sharpening of a ypencil of larger diameter.

the right in Figs. 1 and 2, Fig. 4, is a detail view showing the blade on an enlarged scale, Fig. 5, is a cross-Section of the blade, Fig. 6, is a cross-section similar to that of Fig. 1, Showing a modication of the Sharpener, Fig. 7 is a plan of Fig. 6, Fig. 8, is a cross- Section similar to that of Fig. l showing a further modification, and Fig. 9, is a section of Fig. 8.

The same letters of reference have been used in all the views to indicate corresponding parts.

Referring particularly to the example illustrated in Figs. 1 to 5 of the drawing, a block e is formed with the usual conical bore a adapted to receive and guide the point of the pencil to be sharpened. At one of its sides the conical portion of the block is provided with a longitudinal slit through which the edge of the blade c pro- Vjects substantially tangentially into the conical bore a, as is common in pencil sharpeners of the type shown. Adjacent to the said slit there is formed a bearing face b for the blade 0. The latter consists of a strip of very thin metal, so that it can adapt itself to any form of the bearing b, whether the same be straight as is shown in the drawing, or curved for the purpose of forming a hollow or curved point on the pencil. The blade c is held in place by any preferred means. To show what may be done, I have Shown a U-shaped clamp d which is adapted to be slipped over that portionof the block c which forms the bearing for the blade c so as to clamp the blade on the block e, and if desired the said clamp may be hinged with one of its ends to the'block e. In securing the blade on'its bearing b, itis first placed on the same, whereupon the clamp 0l is slipped over the same. Or the Vclampis rst placed on the block andthe" blade` is slipped under the-same, Vfrwhich purpose theblade is made somewhat longer*y Vthan the block e, so that its ends projectingVV beyond the end s Qf theblock provide4 a suit`-" ablemeans `toholdfthe blade. However, theYK methody of first removing the `clamp d is deemed preferable, particularly where blades,M

are` used. which are formed. with a. .cuttingA edge onfboth'. sides, because Ywhen inserting are* blade, more' Qin :dani I Figs.V` A' and '5L VAs shown` the blade is formed with'two cutting edges. In order-tov I better protect Vthe' .edge-ofthe blade which for'the time is placed inside the bearing b, I'

preferitoV taperthe ,face ofthe bearing.l b away 'from the adjacent face of the clampd, as is shown in Fig..1f,- so thatthe rear edge Y ofthe .bladefc/ is'freely disposed in a hollow space, and Ythe" blade is fin` contact .with -the Vclamp' dv atyitscentral ,.portionvonly. The

rearedge ofthe blade bears on a shoulder formedby the bearing b, so Vthat the blade -f can easily be adjusted. f

Y p yBy using thi blades asdescribed I am en`V abledJto` `supply alarge .number of ysuch blades with the pencilr Sharpenerl and to storev thelsanie within the latter. A construction f of the Sharpener which answersthis purpose has been illustrated in Figs. Gand ,7 'of the f drawing. The construction off'. the sharpener is substantially the sameas that shown inlfigs. -1 to 5, with Vthe exception'that the bladeis not heldin place by means of aA clamp d embracingthe block c from opposite sides, but by means of a plateY f which is .securedto the block in'any suitable way, 'and whichY With `the bearingY face Z) provides a cavity for the blade the formV ofwhich is substantially the same-as that ofthe correspending cavity of the block e shownv in Figs. v1 to,5. At aV suitable part of the block @,fin' the example shown on theV side opposite Y the plate jf, I provide a longitudinal hole g which extends through the block from one endfto vthe'opposite end. Preferably the wal-lofthe hole g is formed with a longitudinalslotl z'. The hole `g provides a suitable j space for storing a number of blades in the Sharpener, and thesaidjblades are held within thesaid hole by means of a spring 71, adapt- Aedto force theblades against the slotted wall l of the hole, so that v-the blades are held withi inthe-hole by friction. i rIhe number ofthe bladesn which can be'stored within the Yhole g depends on the thicknessjof the same, and I have found,-` that six, blades can easily be placedgwithin 'the ,Said hole. By thus Asup-V p'ly'ing alarge number of blades'with the Sharpener which Yare, always. at' hand the Sharpenerf is. made particularly useful, jbecause the cutting edges 'of' the blades 'become ""diilla'ftr a comparatively short time of use, and theo'wnerof the same is now in a posi 'tion `to replace a dull blade by another one, without yhaving recourse to a mechanic. In nthe example illustrated the hole g is open at serted jfromV onedend after first pressing the -spring h backwardy through the slot z'. But I wish it to be understood, ythatmyinvention is, not limited to the formof theblade receptacle shown.A l s p In'Figs. 8 and 9 I haveshown an"exa1nple ofa sharpener'which i's constructed in a similary wayas that shown in Figs. 6 and 7,

and whichis also providedwith a hole or cavity g 'for' the reception of a numberof blades. In -the constructionAk shown the said cavity is formed by a part of4 a U-shaped clamp d embracing the block e from both sides, and constructedin the same way as the correspondingclamping element` shown in Figs.v l'to 5. In-addition to the parts previously described, the YSharpener isformed with a IangeMproviding'an extension of the conical `portionlarl of the block @and the said -flange is adapted lto receive a sleeve lc providing a' suitable guide for the end of the pencil. By `v`thus v,providing the Sharpener with a 'sleeve 7c I am enabled to use the same for sharpeningpencils of different strength. vIf it is desired tosharpena encil of small diameter, Luse vmy'improve 'sharprner in the formshown in Fig."9. If however the diameter of the -pencil is large, I irst reymove the'.` sleeve oiso that the pencil is guidedwithin 4the -bore' of ther ange m. In orderwto more easilyadjust the blade on its bearing face b' I provideprojections onr both sides of the same' which form a suitable guide. .V

In-the foregoing I have described the blade as being flexibleA so fas to adapt itself to any form of the bearing face b, for example to a curved bearing face. For this purpose Iy construct the blade of a thin strip ofmetal, and I have found that I can reduce'the thickness of the blade so far as to two tenths of one` millimeter. Thereby I obtain an exceedingly flexible blade the cost of which is considerably lower than that of the blades nowin use. Besides I am able to supply a large number of' such blades with the Sharpener, which can easil be kept within the hollow or cavity g o the same. I have also found thatthe life ofthecutting edge is longer when using V`a -thin blade.

' I claim hereinA as myinvention:

l. In-a pencil sharpener,.a body ortion provided with a substantially conicaopening to receive a pencil to be sharpened, said body portion having one side thereof recessed, a blade disposed within said recess tobe approximately. flush with the surface of said side, a substantially U-shaped bracket to straddle said body-portion and hold the '-bothends, s that the blades can easily be in! blade in place, and said U-shaped bracket being removable by a lateral movement of the same with relation to said body portion.

2. In a pencil Sharpener, a body portion provided with an axial opening to receive a pencil to be sharpened, one side of said body portion being provided with a longitudinally extending recess having its bottom wall inclined downwardly away from the axial opening, a blade having both longitudinal edges sharpened arranged within the recess, and a U-shaped bracket straddling said body portion and engaging said blade at its longitidinal center only, to hold the same in p ace.

3. In a pencil Sharpener, a body portion provided with an axial opening to receive a pencil to be sharpened, a blade arranged upon said body portion to coperate with said axial opening, a U-shaped bracket adapted to straddle said body portion to hold said blade in position, and said U-shaped bracket being adapted to be positioned upon said body portion by a lateral movement of the same with relation to said body portion. In testimony whereof I hereunto aix my signature in the presence of two witnesses.

ERNST WEILER.

Witnesses WOLDEMAR HAUPT, HENRY HASPER. 

